Variable override

[Harri Porten]

Hi again,

I just looked at the following code in JavaScriptCore'S
VarDeclNode::evaluate() function:

    // already declared? - check with getDirect so you can override
    // built-in properties of the global object with var declarations.
    if ( variable.imp()->getDirect(ident) )
        return Value();

I am aware of the difference between hasProperty() (what KJS uses) and
getDirect(). But I don't quite understand the difference this change makes
here. After all VarDeclNode::processVarDecls() uses hasProperty() and will
"put" an Undefined() value into the variable object. In fact I wonder why
both versions of the libraries do have to make the check twice at all.

I've tried to come up with a test case demonstrating a difference in
behavior but I failed. I tried

 var NaN;
 document.write(NaN);

which returns the expected value of "undefined" in KJS. Could anyone
explain the purpose of above change (except speed differences) or provide
some sample JS code where the change makes a difference?

Thank you,

Harri.